Homeostasis

Question 1

What is a tissue

Answer 1

A tissue consists of a series of similarly specialised cells that perform a common function

Question 2

What are the four major categories of tissues

Answer 2

Epithelial , muscular , connective,nervous

Question 3

What are epithelial cells and what do they help with in the body

Answer 3

Consist of tightly packed cells forming a continuous layer.

They serve in protection (skin)
Secretions (glands)
Absorption (Lines GIT)
Excretion and filtration (kidney)

Question 4

What is connective tissue and what functions does it serve

Answer 4

They are relatively sparse cells in an extracellular matrix

Binds organs and provides support and protection in :
Fibrous tissue
Adipose tissue
Cartilage
Bone
Blood

Question 5

What is muscular tissue and what functions does it serve and what are the three types

Answer 5

Muscle tissue is composed of muscle fibres , it helps in movement.

The three types include:
Skeletal muscle
Smooth muscle
Cardiac muscle

Question 6

What is homeostasis

Answer 6

The relative constancy of the body’s internal environment.

Question 7

How is homeostasis maintained

Answer 7

It is maintained around a set point via negative feedback

Question 8

Which systems control homeostasis

Answer 8

The nervous system
The endocrine system

Question 9

What is the function of Oligodendrocytes

Answer 9

They from the myelin sheath around the axons of the neurons spreading its membrane around the axon which insulates and increases the speed of conduction

Question 10

What is the difference between oligodendrocytes and Schwan cells

Answer 10

Oligodendrocytes are in the cns whereas schwan cells are in the peripheral nervous system

Question 11

What is the function of astrocytes

Answer 11

They provide support to the neurones
Structural
And metabolic (buffer the amount of k+ in the extracellular space)
They also have foot processes

Question 12

What is the function of microglia

Answer 12

They are the immune cells of the cns

Question 13

What is the four parts of the neuron

Answer 13

Cell body
Dendrites
Axon
Axon terminal

Question 14

What is the main function of
Cell body

Answer 14

Contains
Nucleus
RER
Mitochondria

Question 15

What is the main function of
Dendrites

Answer 15

Outgrowths from cell body that receives inputs from other neurons

Question 16

What is the main function of
Axon

Answer 16

Nerve fiber extending from axon hillock which carries the action potential , contains microtubules

Question 17

What is the main function of
Axon terminal

Answer 17

Contains the synapse which works by releasing neurotransmitters

Question 18

What are the three functional class of neurons

Answer 18

Afferent
Efferent
Interneurons

Question 19

What is the function of afferent neurons? (Sensory)

Answer 19

Transmit information to the CNS and have sensory receptors at the peripheral end

Question 20

What is the function of afferent neurons?
(Motor)

Answer 20

Transmit information from the CNS to the effector organs or other neurons .

Question 21

What is the function of interneurons?

Answer 21

Transmit information from neuron to neuron , are exclusively in the CNS, they make up most neurons

Question 22

What does the cns consist of

Answer 22

Brain and spinal cord

Question 23

What does the peripheral nervous system consist of

Answer 23

Nerves and ganglia outside the cns

Question 24

What is the function of the Endocrine system?

Answer 24

The Endocrine system works in coordination with the nervous system to maintain homeostasis

Question 25

Explain the processes for peptide and steroid hormones

Answer 25

Peptide hormones bind to a receptor at the cell membrane, causing a second messenger, cascade, e.g. production of Camp e.g.parathyroid hormone. They cannot cross the cell membrane

Steroid hormones are lipophilic and therefore can cross cell membranes. The receptor can be within the cell, steroid hormones result in hormone receptor complexes that activate DNA and protein synthesis. steroid hormones can also have receptors at the cell surface acting through second messenger systems e.g. aldosterone